Thales of Miletus

Thales of Miletus (624 BC-546 BC) was a Presocratic Greek philosopher, mathematician, and astronomer from Miletus in Asia Minor. Aristotle regarded him as the first philosopher in the Greek tradition, and he was the first Westerner to engage in scientific philosophy.

Biography
Thales of Miletus was born in Miletus in Asia Minor in 624 BC, coming from a distinguished family of remote Phoenician descent. Thales became an astronomer, predicting the solar eclipse of 28 May 585 BC, describing the position of Ursa Minor, believing that using constellations would be a useful guide for sea navigation, and calculating the duration of the year and the timings of the equinoxes and solstices. Thales was known to explain natural objects and phenomena by theories and hypothesies instead of using mythology to explain the world and the universe, and he believed that the nature of matter consisted of water. In mathematics, he used geometry to calculate the heights of pyramids and the distance of ships from the shore. Thales used deductive reasoning in geometry, leading to Thales becoming the first man credited with making a mathematical discovery.

Thales used his prediction of the weather to become a wealthy olive businessman, and he also became a politician, supporting the Lydian king Croesus against the Persians. Thales supported the creation of an Ionian state after the region was freed from Croesus' defeated army, but Miletus received favorable terms from Cyrus the Great, and it ultimately decided against joining the independent Ionian league.